Can you test a TE module with an ohmmeter? No - the DC voltage that a standard ohmmeter applies will cause a temperature change (Peltier Effect) which will in turn cause a voltage to be generated (Seebeck Effect) which will cause the ohmmeter to read strangely (drifting, and even a 'negative' resistance. So, then use the "diode test" position on the ohmmeter? No - even though a TE module is constructed of an array of N and P doped semiconductors there isn't an actual diode junction. A resistance test can be made with an LCR meter which measures resistance using an AC voltage.

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